The changing of the Republican guard is indicative of the party's ideological drift

THE events of September 11th wrought many changes in America, great and small. The announced resignation this week of Dick Armey, the number two in the hierarchy of the House of Representatives, sounds like a small change, but symbolises a bigger one.

Mr Armey, the House majority leader, came to political prominence at a time when Big Ideas mattered. He wrote most of the “Contract with America”, the manifesto of Newt Gingrich's revolution, which swept the Republicans to power in 1994; and many of his beliefs—notably the merits of a flat tax—have gone from the wacky to the debatable. Mr Armey helped persuade the House not to reverse any of George Bush's tax cuts as part of the proposed post-September 11th stimulus package.

But Big Ideas about small government look odd at a time when public trust in government has tripled, and when Mr Bush shuns much of the Gingrich legacy. September 11th has also rendered incongruous the “leave-us-alone” strain of Republicanism that Mr Armey exemplifies. Osama bin Laden didn't leave America alone. He challenged the isolationist strain that occasionally surfaced in Mr Armey, who once joked that he had been to Europe and didn't need to go again. In that sense, September 11th finally ended the revolutionary strain of Republicanism.

What follows him? In personnel terms, the probable answer is Tom DeLay, the majority whip and number three in the hierarchy. Like Mr Armey, Mr DeLay is a Texas conservative (from the Houston suburbs; Mr Armey is from north Dallas). But he is much more confrontational—he is known as “the Hammer”—and would tighten the conservatives' hold on the Republican party's congressional leadership.

This is a prospect that might yet encourage moderates to run against him, touching off an intriguing battle for the direction of the party just at the time that it will be struggling to hold on to its narrow majority in the 2002 mid-term election. Mr DeLay's putative promotion would matter in another way: if he won, the party would lose his day-to-day vote-counting wizardry. He has been the most successful whip Congress has seen for a generation.

The bigger question is what follows Mr Armey ideologically, if anything. This week the House and Senate compromised on a mushy education-reform bill that drops vouchers, increases spending and boosts the federal role in educational testing. The bill shows how much the administration has parted company with the likes of Mr Armey, who wanted to abolish the Department of Education and provide vouchers for all children in Washington, DC's public schools.

That was inevitable: the Republican revolution is long gone. What is less clear is what there is to take its place, except tax cuts. In the summer it seemed that the administration had failed to define what “compassionate conservatism” meant, was running out of domestic policy ideas and needed some sort of second wind. Perhaps it still does, but there are few signs the administration is worried. In the wake of September 11th, Big Ideas about domestic policy seem to matter less and less. No wonder Mr Armey felt it time to retreat.